In blasting operations, detonators and explosives are buried in the ground, for example, in holes (e.g., bore holes) drilled into rock formations, etc., and the detonators are wired for external access to blasting machines that provide electrical signaling to initiate detonation of explosives. Electronic detonators have been developed which implement programmable delay times such that an array of detonators can be actuated in a controlled sequence. Such electronic detonators typically include an internally stored unique identification number, referred to herein as a detonator serial ID number, and logger devices can be used to program individual electronic detonators with a corresponding delay time according to a blasting plan. Within a given blasting plan, each detonator may be assigned a “detonator number” or “detonator ID”, typically corresponding to a given location or position within a blasting site. In many applications, a blasting site can include hundreds or even thousands of electronic detonators located in a large number of holes, which are referred to herein as positions.
Electronic detonator data for a given blasting site is often logged using one or more loggers, which do not include the capability to fire the detonators being logged. In certain contexts the logging may be performed many weeks or months before blasting occurs, and the electronic detonators may be logged one at a time as they are individually connected to the logger device. Logging, moreover, can involve programming delay values into the individual detonators, and may further involve assignment of the detonator ID for a given blasting plan. Certain electronic detonators have been developed, in which logging of electronic detonators may involve an operator connecting each detonator, and pressing buttons or keys on the logger to read the detonator data, which can include the serial ID number, any assigned detonator ID according to a blasting plan, as well as any delay time. Conventional electronic detonator logging can be time-consuming, with the user being required to connect each detonator, interact with the user interface of the logger to initiate individual read operations, as well as any programming and programmed data verification operations, typically involving navigating through prompt screens on the logger. In a large blasting operation having thousands of detonators, conventional logging can take several hours, even where multiple loggers are used, and this process is further lengthened if the delay time needs to be program specifically at each detonator according to a blast program, where the delay programming typically involves several additional keystrokes per detonator.
Thus, conventional electronic detonator logging processes are time-consuming, and thus costly in terms of manpower. Optical scanning of tags or other visible indicia on a detonator is possible, and sometimes quick, but there is no electrical interface in such technology between the logger and the electronics inside the detonator. Moreover, at the end of logging, the detonators cannot be checked electrically to make sure they are all present on a branch line where only optical scanning of tag data is used. In certain situations, delay times can be downloaded to a logger, for example, based on a logical time sequence, and the logger is subsequently connected to the individual electronic detonators and is used to program the corresponding delay times to the individual detonators during logging. Again, however, conventional loggers require an operator to initiate multiple keystrokes to program the delay times and upload the detonator data into the logger, even where the delay time is obtained from memory.
Furthermore, situations may arise where conventional logging is performed on electronic detonators, where the detonators are programmed individually with their respective delay times, but the logger used to log these electronic detonators may be lost, or its internal detonator data may be corrupted or damaged. In such situations, it is common to again log the electronic detonators (e.g., one at a time, or by accessing a single circuit to which multiple detonators are connected) in order to retrieve all the detonator data for subsequent transfer to a blasting machine. However, even where no delay programming is involved, such logging using conventional loggers requires an operator to manipulate the logger user interface keys or buttons several times for each electronic detonator. Accordingly, there is a need for improved electronic detonator logging and delay programming techniques and apparatus to facilitate expeditious and safe logging of detonator data.